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Risks and failures caused by hyaluronic acid injection



Risks and failures caused by hyaluronic acid injection

Hyaluronic acid is one of the substances produced in the body and has a function to keep the skin elastic and moisturized due to its high water retention capacity, but the amount of hyaluronic acid produced decreases with aging . Therefore, it is hyaluronic acid injection that intentionally increases the amount of hyaluronic acid from the outside .

Hyaluronic acid is a substance that is originally present in the body, and since the injected hyaluronic acid is gradually absorbed into the body and has no lasting effect, hyaluronic acid injection can be said to be one of the easy treatments.

However, while it is an easy procedure, it carries various risks . In order not to cause a risk, the guideline for the injection amount and the layer of skin to be injected are set , but if you know what to do in the unlikely event of a failure, you can receive hyaluronic acid injection with confidence. I will.

Ingredients and characteristics of hyaluronic acid

Hyaluronic acid injection in cosmetology acts on various parts such as the forehead, temples, nose, marionette line, and chin to improve wrinkles and sagging due to aging , increase the volume of lips and chest, and contour of the chin and nose. Used for formation .

Hyaluronic acid is a substance originally produced in the body and is distributed in various parts such as skin, joints, eyes and hair. Since it can retain about 6L of water per 1g of hyaluronic acid, it has the role of retaining water in the body and moisturizing the skin .

However, hyaluronic acid-producing dermal fibroblasts begin to decline in activity with age . Hyaluronic acid production is reduced, the water content of the skin is reduced and the skin becomes dry, which causes the skin to lose its elasticity and lead to wrinkles and sagging. Therefore, injecting hyaluronic acid from the outside leads to improvement of wrinkles and sagging. I can.

In addition, by using hyaluronic acid, which has a higher viscosity and is harder than hyaluronic acid used for wrinkles and sagging, it is possible to increase the volume of lips and chest and to form the contour of the nose and chin.

However, hyaluronic acid is absorbed into the body over time, so it is necessary to inject hyaluronic acid regularly to maintain the effect of hyaluronic acid.

Hyaluronic acid is a substance originally found in the body, but if the injection amount or injection location is incorrect, it can lead to serious conditions .

Risks due to impaired blood flow and nerve compression

When injecting hyaluronic acid, if the blood vessels are indirectly compressed or if hyaluronic acid accidentally enters the blood vessels, the hyaluronic acid may become a blood clot and cause blood flow disorders . When blood flow is impaired, blood cannot reach where it is needed, which can lead to serious problems.

Injection site where blood flow disorder is a concern ... Near the eyes, nose, forehead, nasolabial fold


The external carotid artery, which delivers nutrients to the skin and scalp, and the internal carotid artery, which delivers nutrients to the cerebrum, pass near the eyes.

If a blood clot forms in the internal carotid artery that connects to the brain, it may cause a stroke such as a cerebral infarction that clogs a blood vessel or a cerebral hemorrhage or subarachnoid hemorrhage that breaks the blood vessel .

The following symptoms may occur suddenly as a precursor to a stroke.

  • Slurred speech does not turn
  • Numbness or paralysis of limbs
  • Words don't come out
  • Mouth does not close
  • A feeling of strangeness on the face
  • headache

If these symptoms are left untreated , speech disorders and paralysis may remain as sequelae , which may lead to serious situations, so please consult a medical institution immediately.


The internal carotid artery is branched into the ophthalmic artery (cancer domyaku), which not only carries nutrients to the cerebrum but also delivers nutrients to the eyeball and optic nerve. Therefore, when a blood clot is formed , the eyeball and optic nerve at the tip of the blood clot It may stop working and lead to blindness .

The following symptoms are signs of blindness.

  • Sudden loss of vision
  • sweating
  • nausea
  • headache
  • Things look double
  • Difficult to move the eyeball

It is said that the deterioration of eyesight caused by hyaluronic acid can be cured or slightly injured by treating it within 1 to 1.5 hours after the above symptoms occur . If you feel any discomfort after the hyaluronic acid treatment, please consult a medical institution immediately.

Necrosis of the skin

Hyaluronic acid-induced sebum necrosis can occur primarily by injecting hyaluronic acid into the glabellar, nose tip, and nasolabial fold . It occurs when blood vessels are compressed or blood clots block blood flow, preventing blood and nutrients from reaching the tissues beyond the blood vessels.

When blood flow disorder, which is suspected to be necrosis of the skin, occurs, the color of the skin becomes white and changes to red, purple, and black. If you notice any abnormalities in the eyebrows or the tip of your nose, or if the color becomes unnatural, please consult a medical institution immediately.


It is a symptom that occurs mainly when injected into the temporal region or forehead, and in rare cases, you may feel pain that causes the head to tighten . It is caused by pressure on tissues and nerves by the injected hyaluronic acid , but it tends to subside in 2 to 4 days .

Also, if you experience headaches when injecting into areas away from your head, such as your nose or glabellar, you may have impaired blood flow. In that case, there is a risk of stroke, blindness, and skin necrosis, so please consult a medical institution.

Risk of overinjection

Since there are individual differences in the skeleton and fat mass, it is necessary to adjust the injection volume in ml units when injecting hyaluronic acid . The injection is adjusted to an appropriate amount, but if the result is an overinjection of hyaluronic acid, the following symptoms may occur.

Feeling of tension

By injecting hyaluronic acid, the volume of tissues present in the body increases rapidly and pushes up the skin, which may pull the skin and make the skin feel taut . The higher the amount of hyaluronic acid, the stronger the skin feels more taut than when the proper amount is injected.


Hyaluronic acid is absorbed by the body over a period of 1 to 2 years when an appropriate amount is injected . However, if you inject more than an appropriate amount and hyaluronic acid remains in the body for a certain period of time, a collagen film will be formed around the hyaluronic acid , and the hyaluronic acid will not be absorbed by the body and may become a lump .

Risk of hyaluronic acid flow

When injecting hyaluronic acid into the nose or chin, hyaluronic acid may flow around the nose or chin.

Hyaluronic acid has different hardness depending on the size of the particles. The larger the particles, the harder it becomes, and the smaller the particles, the softer the hyaluronic acid.

In hyaluronic acid injection, the treatment is performed using hyaluronic acid whose hardness varies depending on the desired treatment effect and the injection site .

By using hard hyaluronic acid, it is possible to form contours that shape the nose and chin, but if you inject soft hyaluronic acid that is used for wrinkles and volume up during contouring, it will have the original shape. Hyaluronic acid may flow from the injection site under the pressure of the skin trying to return to.

Areas where soft hyaluronic acid is suitable

Soft hyaluronic acid is suitable for areas such as lips and chest that you want to finish softly, not unnatural hardness when touched .

Applicable parts ... Chest, lips, forehead, cheeks, nasolabial fold

Areas where hard hyaluronic acid is suitable

Hard hyaluronic acid is suitable when you want to contour the nose and chin . Injecting hyaluronic acid into the tip of the nose, where blood vessels and nerves are intricately intersected, is not recommended because it may accidentally enter the blood vessels or indirectly compress the blood vessels . ..

Risk of allergies

In rare cases, hyaluronic acid injection may cause urticaria (urticaria) and anaphylactic shock such as dyspnea, rash, and decreased blood pressure due to allergies .

Since hyaluronic acid is a substance that is originally produced in the body, hyaluronic acid itself has few allergic factors and tends to cause less allergic reactions .

If you are wondering if you have an allergic reaction, you can take a hyaluronic acid allergy test. If you take an allergy test, you may have symptoms of an allergic reaction immediately afterwards, or you may have symptoms after a period of about one week, so take the allergy test one week before the scheduled treatment date .

Hyaluronic acid injection volume and injection layer to avoid risks and failures

Since various blood vessels and nerves are complicatedly present on the face, aftereffects such as blindness may remain due to incorrect injection amount and injection location, so the procedure should be performed carefully.

Estimated injection volume set to avoid risk

For hyaluronic acid injection, a guideline for the injection amount is set to avoid risk. However, the appropriate amount for an individual depends on the skeleton and amount of fat that differ from person to person .

Injection site Estimated injection amount
Temporal region 0.2ml ~ 0.5ml
Forehead 0.1m ~ 0.3m
Eyebrow tail 0.1ml ~ 0.2ml
Buggy eye lid * 0.1ml ~ 0.3ml x 3 times
Inside cheek, bow 0.1ml ~ 0.3ml
Cheekbone ridge 0.2ml ~ 0.4ml
Below and outside the cheekbone 0.2ml ~ 1.0ml
Inside below the cheekbone 0.2ml ~ 0.5ml
Nose root / back of nose 0.1ml ~ 0.2ml x 3 times
Nose tip / ala of nose 0.1ml ~ 0.5ml
Front of ear 0.5ml ~ 1.0ml
Upper and central part of nasal lip groove 0.1ml ~ 0.4ml
Lower part of nasolabial fold 0.1ml ~ 0.2ml
Lips / philtrum 0.05ml ~ 0.1ml
Upper lip / corner of mouth 0.1ml ~ 0.2ml
Lower lip 0.2ml ~ 0.4ml
Marionette line 0.1ml ~ 0.4ml
Chin 0.5ml ~ 1.0ml
Face line groove 0.1ml ~ 0.5ml
hand 0.1ml ~ 0.4ml

Injection site and injection depth defined to avoid risk

Injection site Injection depth
Temporal region On the periosteum
Forehead On the periosteum
Eyebrow tail On the periosteum
Buggy eye lid * On the periosteum
Inside cheek, bow, ridge On the periosteum
Sublateral and medial cheekbones Subcutaneous tissue
Nose root, nose back, nose wings On the periosteum
Nose tip Subcutaneous tissue
Front of ear Subcutaneous tissue
Upper part of nasal lip groove On the dermis layer or periosteum
Central / lower part of nasolabial fold Dermis layer
Corner of the mouth Dermis layer
Upper lip Dermis layer
Philtrum / lower lip Subcutaneous tissue
Marionette line Dermis layer
Chin Supra-periosteal or subcutaneous tissue
Face line groove Supra-periosteal or subcutaneous tissue
hand Subcutaneous tissue

* Buggy eyelids are protrusions of fat that look like bears and refer to sagging lower eyelids.

Skin structure and layer of skin infused with hyaluronic acid

From the skin to the bone, the epidermis, dermis (layer), subcutaneous tissue (subcutaneous fat), muscle, periosteum, and bone are layered in this order from the outside, and support that has the function of fixing the skin of the face from the dermis to the periosteum. The ligament is present.

There are three layers on which hyaluronic acid can be injected: the dermis, the subcutaneous tissue, and the periosteum . The layer on which hyaluronic acid is injected differs depending on the purpose of the treatment and the treatment site, such as whether it is for improving wrinkles or sagging or for contouring.

In addition, in order to improve wrinkles and sagging and form contours by injecting hyaluronic acid, it is necessary to roughly divide into the following three, and since the tissue that is easily weakened differs depending on the site, bones are injected at each site. Where it should act on tissue, fat, and supporting ligaments is different .

  • Bone tissue reinforcement
  • Reinforcement of supporting ligaments
  • Increased fat volume

If you want to improve wrinkles and sagging, you need to act on bone tissue, supporting ligaments, and fat . When the bone tissue and ligaments that support the skin and fat weaken with age, the skin and fat that have no source of support cannot resist gravity and hang down, causing sagging and wrinkles. Reduced fat volume also causes wrinkles and sagging.

In addition, when contouring the nose and chin, it acts on bone tissue or fat to form it.

Inject hyaluronic acid onto the periosteum to reinforce bone tissue

Osteoclasts (Hakotsusaibo) destroy bone tissue in the frontal bone, temporal region, orbit (cancer), and jaw as they age, breaking down old calcium and collagen and draining them into the blood. It is said that bone resorption progresses, bone shrinks and tends to decline.

By injecting hyaluronic acid over the periosteum above the bone in areas where the bone is prone to weakening, it replaces the resorbed bone and leads to improvement of firmness and sagging .

In addition, the method of injecting hyaluronic acid onto the periosteum provides the foundation for the bone to support the hyaluronic acid, and the hyaluronic acid is fixed to the bone. It is said that there is less risk of the injected hyaluronic acid moving or spreading, so it is also suitable for treatments that require volume up.

Inject hyaluronic acid onto the periosteum to reinforce the supporting ligaments

The face has supporting ligaments of the orbital ligament (TL1), buccal ligament (TL2), maxillary ligament (TL3), and mandibular ligament (TL4).

When the muscle contracts due to aging, the skin that is connected to the muscle is also pulled at the same time, but the skin that is connected to the supporting ligament is fixed to the pulled skin because it is fixed by the supporting ligament. It distorts between the skin and lifts it, causing wrinkles and sagging.

In addition, the supporting ligaments that have weakened with age can no longer support the skin and adipose tissue, which makes the skin unable to resist gravity and may cause wrinkles and sagging . Therefore, by injecting hyaluronic acid onto the periosteum just below the supporting ligament , the supporting ligament can be supported .

Inject hyaluronic acid into the dermis and subcutaneous tissue to increase fat volume

The part of the face where the volume of fat is likely to decrease is said to be the central part when the face is divided into three vertically , which is the cheek, nose, and the chin, which is the groove extending from the nose to the upper lip. Therefore, when aiming to improve wrinkles and sagging in these areas, it is possible to improve by injecting hyaluronic acid into the subcutaneous tissue, which is the fat layer .

In the case of breast augmentation, it is recommended to inject hyaluronic acid between the pectoralis major muscle and the mammary gland, which have poor blood flow.

Hyaluronidase that can break down hyaluronic acid

In hyaluronic acid injection, the amount of hyaluronic acid to be injected and the layer of skin to be injected are determined in order to avoid failures, risks and side effects, but depending on the skill of the doctor, the duration of the effect may be shortened or the result of the treatment effect. It is also a treatment that changes .

Therefore, in the unlikely event that a serious situation occurs or the expected result is not achieved , hyaluronic acid is dissolved with "hyaluronidase" that decomposes it, and measures are taken to restore it to its original state.

Hyaluronidase is a degrading enzyme that breaks down hyaluronic acid into water and carbon dioxide and absorbs them into the body.

However, hyaluronidase does not exist because of the ease of hyaluronic acid injection . Please know as a last resort

Types of hyaluronidase

There are four main types of hyaluronidase.

Formulation name Derived ingredients Approval
Hylenex Human FDA
Vitrase Sheep FDA
Amphadase cow FDA
Hyalase Sheep None

Many hyaluronidases have been approved by the FDA, which is the Ministry of Health, Labor and Welfare of Japan. In the United States, not only human-derived Hyaluronidase, but also animal-derived Vitrase and Amphadase are used. However, animal-derived hyaluronidases are more likely to have an allergic reaction than when human-derived ingredients are used . Therefore, in Japan, there is a tendency to use High Renex, which is manufactured with human-derived ingredients.

Precautions for hyaluronidase

Hyaluronic acid embolism

Hyaluronidase can break down hyaluronic acid, but if a blood clot forms in an artery and hyaluronidase is injected, a small mass of hyaluronic acid broken down in the blood vessel may cause re-embolism, so medical treatment for several hours. You have to stay at the institution and see what happens.

Hyaluronic acid reinjection 1 month later

It is said that it takes one week to one month for hyaluronic acid to completely dissolve after injecting hyaluronidase. Many medical institutions recommend re-injection of hyaluronic acid after the hyaluronic acid is completely decomposed, so after injecting hyaluronidase, re-injection of hyaluronic acid should be done for a period of at least 1 week to 1 month. I will .